Conventional systems for transporting passengers/goods such as moving walkways include a band of conveyor pallets which move in a track for the purpose of providing a continuous movement along a specific path. The conveyor pallets are connected to said chain track which moves as a result of a drive system. The drive system normally consists of a chain of conveyor plates, cogged wheels, a shaft and an electric geared motor. The electric motor drives the shaft to which there are integrally attached cogged wheels, which transmit the movement to the links of the chain of conveyor pallets. The conveyor pallets move in the same manner as said chain. The drive system is located at one of the ends of the moving walkway whereas the elements responsible for tensing the system are normally located at the opposite end. The turnover of the conveyor pallets which travel the entire moving walkway in the lower part completing the return trip occurs at these end areas of the moving walkway.
A series of new designs aiming to reduce the maximum machine height has emerged in recent years; the conventional drive system must therefore be modified.
There are several solutions which were chosen according to the walkway concept being used. One of these solutions is described in WO 05042392 from Kone Corporation, according to which the drive system is at least partially located inside the balustrade which is made possible by means of using a flat motor. The drive thus occurs by means of a series of belts or chains which finally drive the chain of pallets which has a short pitch to enable turning over in the small available space, but it otherwise works as a conventional walkway chain.
U.S. Pat. No. 7,341,139 also from Kone Corporation describes the drive of a handrail and its attachment to the pallets drive and motor system. U.S. Pat. No. 7,353,932 from Kone Corporation describes the arrangement of a band of pallets and the possible simultaneous use of two drive motors.
ThyssenKrupp's Spanish patent with application number 200601651 describes a compact walkway based on the concept of a band formed by pallets having a pitch shorter than the conventional ones. This walkway comprises a drive system moving the pallets of a moving walkway through drive chains which directly engage the lower part of the drive link chains. The drive chain has separate drive rollers which are made of deformable and elastic materials. The links of the drive chains are connected to one another by attachment shafts and have teeth and jaws in the lower part to engage the drive chain and the rollers.
ThyssenKrupp's Spanish patent with application number 2009311290 proposes a drive system for driving chainless escalators and moving walkways by means of using a set of roller wheels integral with shafts assembled between the departing and returning sections of the band of steps or pallets and engaging either the steps or pallets directly through engaging formations of said steps or pallets on their inner surface or similar formations present in a chain integral with the band of pallets or steps.
All these applications have the drawback of the limitation of power which can be transmitted by the drives to the band of steps or pallets due to the small available space in comparison with conventional drives, hindering the use of several transmission elements and the suitable reinforcement thereof.
In terms of escalators, most drive systems are still based on the conventional engagement method between a cogged wheel and a roller chain attached to the steps.